TREE MEAN DIAMETER ESTIMATION FROM TERRESTRIAL IMAGES USING DIGITAL CAMERA

摘要

A improved method to determine the wood-yield from a state of current plantation, comprising the steps of acquiring digital photographs by adapting SLR camera of a sample plot having a plurality of trees after the sun-set using a flash gun; analyzing the image acquired at breast-height In respect of profile reading in an image analyzer by considering RGB (Red, Green, Blue) values for every pixel; estimating the reflection capacity of each of the tree-barks within the sample plot in order to measure the ground distance between the camera and the trees including the pixel diameter of the trees; calculating a correction factor for a specific image size including a particular focal length of the lens of the camera; multiplying the correction factor with the determined ground distance which provides the pixel size of each tree at a specific ground distance; multiplying the pixel size with the pixel diameter relating to each tree to arrive at a value representing the actual diameter of the tree; and determining the mean diameter of the trees in a sample plot by adding actual diameter of each tree and dividing the added value by the number of trees located In the sample plot, the mean diameter representing the wood-yield of a forest plantation.[IN-CHE-2010-00361A]